<div class="row">
  <x-button (click)="open('top-start', '上左')">上左</x-button>
  <x-button (click)="open('top-end', '上右')">上右(默认)</x-button>
  <x-button (click)="open('bottom-start', '下左')">下左</x-button>
  <x-button (click)="open('bottom-end', '下右')">下右</x-button>
</div>